1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * Definitions for the UDP protocol.
9 * Version: @(#)udp.h 1.0.2 04/28/93
11 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
16 #include <net/inet_sock.h>
17 #include <linux/skbuff.h>
18 #include <net/netns/hash.h>
19 #include <uapi/linux/udp.h>
21 static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
23 return (struct udphdr *)skb_transport_header(skb);
26 #define UDP_HTABLE_SIZE_MIN_PERNET 128
27 #define UDP_HTABLE_SIZE_MIN (CONFIG_BASE_SMALL ? 128 : 256)
28 #define UDP_HTABLE_SIZE_MAX 65536
30 static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask)
32 return (num + net_hash_mix(net)) & mask;
36 UDP_FLAGS_CORK, /* Cork is required */
40 /* inet_sock has to be the first member */
41 struct inet_sock inet;
42 #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0]
43 #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1]
44 #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node
46 unsigned long udp_flags;
48 int pending; /* Any pending frames ? */
49 __u8 encap_type; /* Is this an Encapsulation socket? */
50 unsigned char no_check6_tx:1,/* Send zero UDP6 checksums on TX? */
51 no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */
52 encap_enabled:1, /* This socket enabled encap
53 * processing; UDP tunnels and
54 * different encapsulation layer set
57 gro_enabled:1, /* Request GRO aggregation */
59 accept_udp_fraglist:1;
60 /* indicator bits used by pcflag: */
61 #define UDPLITE_BIT 0x1 /* set by udplite proto init function */
62 #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */
63 #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */
64 __u8 pcflag; /* marks socket as UDP-Lite if > 0 */
66 * Following member retains the information to create a UDP header
67 * when the socket is uncorked.
69 __u16 len; /* total length of pending frames */
72 * Fields specific to UDP-Lite.
77 * For encapsulation sockets.
79 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
80 void (*encap_err_rcv)(struct sock *sk, struct sk_buff *skb, int err,
81 __be16 port, u32 info, u8 *payload);
82 int (*encap_err_lookup)(struct sock *sk, struct sk_buff *skb);
83 void (*encap_destroy)(struct sock *sk);
85 /* GRO functions for UDP socket */
86 struct sk_buff * (*gro_receive)(struct sock *sk,
87 struct list_head *head,
89 int (*gro_complete)(struct sock *sk,
93 /* udp_recvmsg try to use this before splicing sk_receive_queue */
94 struct sk_buff_head reader_queue ____cacheline_aligned_in_smp;
96 /* This field is dirtied by udp_recvmsg() */
99 /* This fields follows rcvbuf value, and is touched by udp_recvmsg */
100 int forward_threshold;
103 #define udp_test_bit(nr, sk) \
104 test_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
105 #define udp_set_bit(nr, sk) \
106 set_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
107 #define udp_clear_bit(nr, sk) \
108 clear_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
109 #define udp_assign_bit(nr, sk, val) \
110 assign_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags, val)
112 #define UDP_MAX_SEGMENTS (1 << 6UL)
114 #define udp_sk(ptr) container_of_const(ptr, struct udp_sock, inet.sk)
116 static inline void udp_set_no_check6_tx(struct sock *sk, bool val)
118 udp_sk(sk)->no_check6_tx = val;
121 static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
123 udp_sk(sk)->no_check6_rx = val;
126 static inline bool udp_get_no_check6_tx(struct sock *sk)
128 return udp_sk(sk)->no_check6_tx;
131 static inline bool udp_get_no_check6_rx(struct sock *sk)
133 return udp_sk(sk)->no_check6_rx;
136 static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk,
141 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
142 gso_size = skb_shinfo(skb)->gso_size;
143 put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size);
147 static inline bool udp_unexpected_gso(struct sock *sk, struct sk_buff *skb)
149 if (!skb_is_gso(skb))
152 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4 && !udp_sk(sk)->accept_udp_l4)
155 if (skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST && !udp_sk(sk)->accept_udp_fraglist)
161 static inline void udp_allow_gso(struct sock *sk)
163 udp_sk(sk)->accept_udp_l4 = 1;
164 udp_sk(sk)->accept_udp_fraglist = 1;
167 #define udp_portaddr_for_each_entry(__sk, list) \
168 hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
170 #define udp_portaddr_for_each_entry_rcu(__sk, list) \
171 hlist_for_each_entry_rcu(__sk, list, __sk_common.skc_portaddr_node)
173 #define IS_UDPLITE(__sk) (__sk->sk_protocol == IPPROTO_UDPLITE)
175 #endif /* _LINUX_UDP_H */